Contaminant blood cultures are common, representing up to half of all positive blood cultures. D. Bates et al., JAMA 265:363 (1991). Contaminants can in turn lead to unnecessary therapy, such as the administration of antibiotics, and additional testing and consulting. In addition, contaminated blood cultures can result in unnecessarily prolonged hospital stays. Such unnecessary procedures result in excess laboratory fees, diagnostic fees, pharmacy fees, physicians' fees, and hospital fees. Thus, in addition to inconvenience and potential harm to a patient, the true costs associated with contaminated blood cultures can be economically exorbitant.
The increased costs associated with contaminated blood cultures underscores the importance of sterile technique when obtaining blood samples.
Although the importance of sterile technique in the medical field, and in the area of blood sampling and culturing in particular has been known for some time, evidence as presented in the study by D. Bates et al. demonstrates a continued and urgent need for improvements in sterile techniques.
Recent activity in the area of sterile techniques is evidenced in European Patent Application number 89301916.6 directed to anesthesia and antisepsis of the skin. In the European application the use of transdermal delivery of anesthetics having antimicrobial properties is disclosed.
However, the need for sterile techniques for obtaining blood free of contaminants is still unmet.